1. Technical Field
The present invention relates to an electronic document generation system for generating an electronic document, and technology related thereto.
2. Related Art
In technology for generating electronic documents, there are techniques for enhancing the visibility of characters while increasing the compression rate. For example, there is a technique for generating an electronic document in a high-compression portable document format (PDF) based on a scanned image (see JP 2009-141597A, for example).
With high-compression PDF documents, rather than the same compression method being applied to the entirety of image data, for example, a scanned image is divided into a character area and a non-character area, and different compression methods are applied to each type of the regions. To be more specific, image data in the character area is binarized while maintaining high resolution, whereas image data in the non-character area is converted into low-resolution image data without being binarized in order to maintain tone, and is then compressed at a high compression rate (high compression). This generates an electronic document file (high-compression PDF file) with a reduced data amount (file size) while maintaining the readability of characters.
However, with such binarized characters in the character area in a high-compression PDF, there is the problem that jaggies on the outlines of the characters are noticeable in the case of using a slightly lower resolution. A similar problem also occurs in the case where these characters are enlarged and viewed on a monitor.